Proper Understanding of Condensed Nearest Neighbor












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I have a question regarding the Condensed Nearest Neighbors algorithm:
enter image description here



Why am I returning Z, which if I understand correctly, is the array of all of the misclassified points? Wouldn't I want to return the points that were classified correctly? What benefit does this give me in returning all the points I got wrong?










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    1












    $begingroup$


    I have a question regarding the Condensed Nearest Neighbors algorithm:
    enter image description here



    Why am I returning Z, which if I understand correctly, is the array of all of the misclassified points? Wouldn't I want to return the points that were classified correctly? What benefit does this give me in returning all the points I got wrong?










    share|improve this question







    New contributor




    Jerry M. is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
    Check out our Code of Conduct.







    $endgroup$















      1












      1








      1





      $begingroup$


      I have a question regarding the Condensed Nearest Neighbors algorithm:
      enter image description here



      Why am I returning Z, which if I understand correctly, is the array of all of the misclassified points? Wouldn't I want to return the points that were classified correctly? What benefit does this give me in returning all the points I got wrong?










      share|improve this question







      New contributor




      Jerry M. is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.







      $endgroup$




      I have a question regarding the Condensed Nearest Neighbors algorithm:
      enter image description here



      Why am I returning Z, which if I understand correctly, is the array of all of the misclassified points? Wouldn't I want to return the points that were classified correctly? What benefit does this give me in returning all the points I got wrong?







      algorithms dimensionality-reduction






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      share|improve this question







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      asked 2 days ago









      Jerry M.Jerry M.

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          Condensed Nearest Neighbors algorithm helps to reduce the dataset X for k-NN classification. It constructs a subset of examples which are able to correctly classify the original data set using a 1-NN algorithm.



          It is returning not the array of misclassified points, but a subset Z of the data set X.



          CNN works like that:



          1) Scan all elements of X, looking for an element x whose nearest prototype from Z has a different label than x



          2) Remove x from X and add it to Z



          3) Repeat the scan until no more prototypes are added to Z



          Z used instead of X for kNN classification.



          An advantage of this method is decreasing of execution time, reducing a space complexity






          share|improve this answer








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            $begingroup$

            Condensed Nearest Neighbors algorithm helps to reduce the dataset X for k-NN classification. It constructs a subset of examples which are able to correctly classify the original data set using a 1-NN algorithm.



            It is returning not the array of misclassified points, but a subset Z of the data set X.



            CNN works like that:



            1) Scan all elements of X, looking for an element x whose nearest prototype from Z has a different label than x



            2) Remove x from X and add it to Z



            3) Repeat the scan until no more prototypes are added to Z



            Z used instead of X for kNN classification.



            An advantage of this method is decreasing of execution time, reducing a space complexity






            share|improve this answer








            New contributor




            Anastasiia Shalygina is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
            Check out our Code of Conduct.






            $endgroup$


















              2












              $begingroup$

              Condensed Nearest Neighbors algorithm helps to reduce the dataset X for k-NN classification. It constructs a subset of examples which are able to correctly classify the original data set using a 1-NN algorithm.



              It is returning not the array of misclassified points, but a subset Z of the data set X.



              CNN works like that:



              1) Scan all elements of X, looking for an element x whose nearest prototype from Z has a different label than x



              2) Remove x from X and add it to Z



              3) Repeat the scan until no more prototypes are added to Z



              Z used instead of X for kNN classification.



              An advantage of this method is decreasing of execution time, reducing a space complexity






              share|improve this answer








              New contributor




              Anastasiia Shalygina is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
              Check out our Code of Conduct.






              $endgroup$
















                2












                2








                2





                $begingroup$

                Condensed Nearest Neighbors algorithm helps to reduce the dataset X for k-NN classification. It constructs a subset of examples which are able to correctly classify the original data set using a 1-NN algorithm.



                It is returning not the array of misclassified points, but a subset Z of the data set X.



                CNN works like that:



                1) Scan all elements of X, looking for an element x whose nearest prototype from Z has a different label than x



                2) Remove x from X and add it to Z



                3) Repeat the scan until no more prototypes are added to Z



                Z used instead of X for kNN classification.



                An advantage of this method is decreasing of execution time, reducing a space complexity






                share|improve this answer








                New contributor




                Anastasiia Shalygina is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
                Check out our Code of Conduct.






                $endgroup$



                Condensed Nearest Neighbors algorithm helps to reduce the dataset X for k-NN classification. It constructs a subset of examples which are able to correctly classify the original data set using a 1-NN algorithm.



                It is returning not the array of misclassified points, but a subset Z of the data set X.



                CNN works like that:



                1) Scan all elements of X, looking for an element x whose nearest prototype from Z has a different label than x



                2) Remove x from X and add it to Z



                3) Repeat the scan until no more prototypes are added to Z



                Z used instead of X for kNN classification.



                An advantage of this method is decreasing of execution time, reducing a space complexity







                share|improve this answer








                New contributor




                Anastasiia Shalygina is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
                Check out our Code of Conduct.









                share|improve this answer



                share|improve this answer






                New contributor




                Anastasiia Shalygina is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
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                answered yesterday









                Anastasiia ShalyginaAnastasiia Shalygina

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